Separable scissor construction



June 8, 1937. B. STREZOFF 2,033,483

' SEPARABLE SCISSOR CONSTRUCTION Filed Feb. 17, 1956 Patented June 8,1937 UNITED STATES PATENT OFFICE f Bogoia Strezoff, Minneapolis, Minn.

Application February 17, 1936, Serial No.-64,247

3 Claims.

My invention relates to scissor construction and particularly toscissors having one blade readily separable from the other.

Various types of scissors are in use, some having both blades of theordinary straight-edged type trades and professions an individual mayhave use for a number of different types of scissors each of whichincludes one blade of the ordinary straight-edged type.

In such cases it would be highly desirable to have scissors in which oneblade iseasily and quickly separable fromthe other so that onestraight-edged blade may be operatively connected either to a secondstraightedged blade or to any one of a plurality of special blades.

An object of my invention is to provide pivot joint construction forscissors and the like permitting quick and easy detachment of one bladeof the scissors from the other to enable operative association of afirst blade with any one of several second blades. I

Another objectis to provide scissors 'with separable pivot jointconstruction which is snugly fitting and yet free for easy pivoting whenassembled in operative position. P

A further object is to provide such pivot joint structure of simple,rugged and inexpensive construction.

These and otherobjects and advantages of the invention .will more fullyappear from the following description, made in connection with theaccompanying drawing,"wherein like reference characters refer to thesame or similar parts throughout the various views, and in which:-

Fig. 1 is a view of a pair of scissors embodying my invention, theblades being shown in closed position in full lines and one blade beingshown in dotted lines as it appears when swung relative to the otherblade to a wide open position;

Fig. 2 is a view of another type ofblade which may be substituted forone of the blades of Fig. 1.

sist, in general, of a pair of scissor members i and 6 comprisingrespective medial portions 5a and 6a, respective handles 5b and 6b andrespective shearing blades 5c and 6c; the handle and blade of eachscissor member extending in opposite directions from the medial portionthereof and the medial portions of the respective scissor members beingconnected together in crossed pivotal relation. All of the abovedescribed structure is in accordance withv the conventional practiceexcept the pivotal joint which I employ and'which will be described. l

The inner side of the medial portion 6a of the scissor member 6 carriesa pivot stud I of noncircular cross sectionin inwardly projecting normalrelation thereto. While other means could be used, the stud I is securedto the medial portion 6a of the scissor member 6 by means of ascrew-threaded extension la thereof screwthreadedly retained in aninternally screwthreaded apertured portion of the medial portion Go asshown. The head lb of the stud I is preferably of circular shape and maybe slotted; as shown if desired, to facilitate making of'the abovedescribed screw-threaded connection. A jam-nut 1c is placed on the freeend of the stud I as shown.

The stud 1 is of non-circular cross section as above mentioned, and,while various non-circular shapes could be used, I prefer to use a shapesuch as would be produced by taking. a cylindrical stud and removingmaterial to form a pair of diametrically oppositely located parallelflat faces such as the faces 1d. The stud 1 is secured to the medialportion 6a of the scissor member 6 with a line disposed diametricallythereof and parallel to the faces Id displaced by an acute angle from-the longitudinal axis of the-scissor member 6 member 5 is provided witha centrally located circular aperture 8 therethrough for receiving thestud I in journaled relation thereto. The-aperture 8 has adiame'ter'exceeding the longest diameter of the stud 'l only-sumcientlyto'permit the stud 'l to rotate in the aperture 8. Although the head 1bof the pivot stud I may be disposed so as to hear at its innersideagainst the outer side'of the medial portion 5a of the scissormemher 5,. it is preferable that'the outer end of the aperture I beincreasedin diameter to form a circular recess or depression I forreceiving the head ID at least to a portion of the depth of the head Ibas shown. The diameter of the recess t is such that the periphery of thehead I!) and removal therefrom of the stud I and its head Ib. To thisend a notch or slot II is formed in the medial portion Ia of the scissormember I extending from an edge of the member I to the aperture 8 inradial relation to the aperture I. Preferably, the slot It extendssubstantially laterally of the scissor member I toward the right asviewed in the full line portion of Fig. 1. The width of the slot III isnecessarily dimensionally intermediate the longest and shortestdiameters of the pivot stud I and is preferably greater than thesmallest diameter of the stud I only to an extent providing clearancepermitting movement of the stud I through the slot In laterally of thescissor member I when the faces Id of the stud I are parallel to thesides of the slot II. A groove II, for accommodating the head Ib of thepivot stud I, extends from the recess 9 to the edge of the medialportion In of the scissor member'I in co-directional relation to theslot in. The width of the groove II is at least as great as the diameterof the stud head 'Ib and is preferably equal to the diameter of the headreceiving recess 9.

A hair thinning scissor member I2 adapted for association with thescissor member I'in substitution for the scissor member 5 is shown inFig. 2. .The scissor member I2 is identical with the scissor member 5 inits medial portion I 2a and the handle portion I21) and is provided withan aperture 8, recess 9, slot I0 and groove II identical with thosedescribed above in connection with the scissor member I. The blade He isidentical with the blade of the scissor member I except that the cuttingedge thereof is.notched and I formed in accordance with the constructionordinarily found in hair thinning scissors of conventional design. Othersimilar scissor members having various types of cutting edges may beprovided for association with the scissor member 6 if desired. I

In normal use of my scissors the same are manipulated in the same manneras any scissors of conventional design. Within the range of angles atwhich the respective scissor members I and I are disposed rel'ative toeach other in such use the stud I is always so disposed that the facesId are never parallel to the slot I I and hence that the projected widthof the stud I presented to the inner end of the slot I0 is alwaysgreater than the width of the slot III to prevent outward movement ofthe stud I through or into the slot II. In this manner the scissormembers 5 and I are positively retained in pivotal relation to eachother in normal use ofthe scissors. The journaled engagement of thecircular head 1b of the pivot stud I with material defining the sides ofthe circular recess 9 assists'in preventing lateral play.

of the pivotal joint and'its engagement with the material defining thebottom of the recess prevents separation of the scissor members I and 6in the direction of the longitudinal axis of the stud I.

When it is desired to separate the respective scissor members I and tthe same are apart to approximately their wide open position asrepresented .in Pig. 1 by member in full lines and member I in dottedlines. This is a position angularly displaced in the vicinity of 225degrees from the fully closed position of the members I and I. In theapproximately wide open position described the faces Id of the stud Iare parallel to and aligned with the sides of the slot ll so that thestud I may be slidthrough the slot It to disengage one of themembers Iand I from the other. The method of ire-assembly is believed tobeapparent and it should also be apparent that the member I! of. Fig. 2,or any other scissor member having similar construction in its medialportion. maybe substituted for the scissor member I in such re-assembly.

Another form of my separable pivot joint is illustrated in Fig. 5. Inthis form the non-circular pivot stud III is formed integrally with themedial portion Ia of the scissor member I.- The 'pivot stud III and themedial portion Ia. are apertured co-axially of the pivot stud II, thelower portion of the material defining the aperture being internallyscrew-threaded and the upper portion being of slightly increaseddiameter. The pivot stud It is of the same cross-sectional shape anddimensions as the previously described pivot stud I and has flat facesltd. disposed at the-same angle as the faces Id of the pivot stud I. Ascrew I I, having a head Ila. of the same construction as the head lb ofthe stud I, is screw threadedly engagedin the above mentioned aperturewith its head liq disposed in the circular recess 9 of the scissormemberI, A jam nut I lbv is placed on the free end of the screw II. The pivotstud II is, of course, normally journaled in the aperture 8 of thescissor member 5 and disengagement of the pivot stud ill from thescissor member I is accomplished in the same manner as employed indisengaging the pivot stud I of the previously described embodiment ofthe invention. Ad-' justment of the scissors to compensate for wear I iseffected by suitably turning the screw II.

With construction such as described above, it is obvious that scissorsof various types and for various purposes may be readily available withmuch fewer parts than if a separate pair of nonseparable scissors wereprovided for each purpose.

If any scissor member of a set of scissor members such as mine becomesbroken or damaged, it is'not necessary to replace a complete pair ofscissors since a new member may be readily assembled with an old memberof complementary construction. Also separation of the respective membersof a pair of scissors such as mine greatly facilitates easy and accuratesharpening of the cutting edges thereof and where necessary. thecleansing and sterilizing thereof.

While my separable pivotal joint has been 11- lustrated and described asapplied to scissors, it

of construction permitting convenient and rapid changes may be made inthe form, details, proportions and arrangement of the parts, withoutdeparting from the scope of my invention, which, generally stated,consists in a device capable ofcarrying out the objects above set forthand in the novel parts and combinations of parts disclosed and definedin the appended claims.

What is claimed is;- l. A separable pair of scissors having incombination a pair of crossed, pivotally connected scissor elementshaving blade portions adapted to frictionally engage at their edges forshearing effect and a separable pivot joint connecting the medialportions of said elements and including a headed pivot stud projectingfrom the inner side of one of said elements and threaded into saidelement for adjustable clamping action against said other scissorelement, said stud having a non-circular portion adjacent its outer endhaving arcuate bearing surfaces concentric of its axis and havingportions of less radius between said bearing surfaces, said secondscissor element being apertured to receive the cross sectional shapeof.said non-circular stud portion only when said scissor elements aredisposed at an angle to each other outside the normal operating rangethereof and having a substantially circular bearing surface concentricwith the axis of said stud .for engaging the arcuate bearing areas ofsaid stud after said scissor elements are joined and secured together. I

2. A separable pair of scissors having in combination a pair of crossed,pivotally connected scissor elements having blade portions adapted tofrictionally engage attheir edges for shearing efiect and a separablepivot joint connecting the medial portions of said elements andincluding a a headed pivot stud projecting from the inner side of one ofsaid elements and threaded through said element for adjustable clampingaction against said other scissor element, said stud having anon-circular portion adjacent its outer end having arcuate bearingsurfaces concentric of its axis and having portions of less radiusbetween said bearing surfaces, said second scissor element beingapertured to receive the cross sectional shape of said non-circular studportion only when said scissor elements are disposed at an angle to eachother outside the normal operating range thereof and having asubstantially circular bearing surface concentric with the axis of saidstud for engaging the arcuate bearing areas of said stud after saidscissor elements are joined and secured together, and a jam nutthreadedlyengaging the projecting end of said pivot stud and engagingagainst said first mentioned scissors element to retain said studagainst screw displacement.

3. A separable pair of scissors having in combination a pair of crossed,pivotally connected scissor elements having blade portions adapted tofrictionally engage at their edges for shearing effect and a separablepivot joint connect ing the medial portions of said elements andincluding a headed pivot stud projecting from the inner side of one ofsaid elements and threaded into said element for adjustable clampingaction tween said arcuate bearing surfaces whereby said stud may bepassed through said slot. only when the maximum diameter of said studis-substantially parallel to said slot and means for retaining said studagainst screw displacement relative to said first mentioned scissorselement.

BOGOIA STREZOFF.

